Diffraction moire interferometry has been applied to numerous static and slowly changing stress configurations. This technique has now been extended to the study of dynamic loading events, especially to the interaction of dynamic stress waves with such flaws as cracks or with the variations in composition found in composite materials. A pulsed ruby laser was used to provide the rapid (20 ns wide), brilliant, and coherent illumination required for these studies. The technique and several specific applications are described. Key words: Dynamic strain, dynamic moire', pulsed laser, fracture, composites, ceramics.